Inhomogeneity Effect on Solitary Structures in a Magnetized Warm Plasma: Ionization Versus Recombination

Abstract

In a magnetized inhomogeneous warm plasma having ionization/recombination, usual version of the KdV equation is found to be modified by two additional terms arising due to the inclusion of ionization/recombination and the density gradient in the plasma. The density gradient in the plasma shows its dependence on the ionization/recombination rate, ion-to-electron temperature ratio, obliqueness of the magnetic field and drift velocity of the ions. In the considered plasma, only the compressive solitary structures are found to propagate corresponding to two different types of modes. A significant effect of magnetic field and ion temperature is found on these structures in both the cases of ionization and recombination, though these structures show weak dependence on the charge of the ions. Interestingly the solitons with prominent tailing structures are evolved in the plasma under the effect of stronger density gradient and higher ionization or recombination. The tailing structure with bigger size evolves in the plasma in the case of only recombination, suggesting that the exchange/transfer of energy from the main soliton to its tail is on a greater scale in the case of recombination than the case of ionization. There exists a critical value of the ionization rate at which the tailing structure associated with only the fast (not slow) solitary structure is vanished. Similarly, the tailing structure associated with only the slow (not fast) solitary structure is disappeared at a critical value of recombination rate.